1. Field of the Invention
This invention relates to a grass collecting system for a lawn mower having a grass collecting duct for transmitting grass clippings reaped by a mower unit to a grass catcher, the grass catcher being supported by a lift mechanism to be vertically movable relative to the mower unit.
2. Description of the Related Art
In an environment where grass clippings reaped by the mower unit cannot be discharged directly, it is necessary to store the grass clippings temporarily in the grass catcher through the grass collecting duct. The lawn mower having such a grass collecting system, when a certain amount of grass clippings accumulates in the grass catcher, runs to a predetermined grass clippings dump area, and discharges the grass clippings from the grass catcher. In time of discharge, the grass clippings could fall off from the opening of the grass catcher and scatter outside grass clippings dump area before the grass catcher reaches a predetermined position. Various contrivances have heretofore been proposed with a view to avoiding such inconveniences.
For example, a grass collecting apparatus has a lid for closing an opening of a grass catcher, and a guide switchable by the lid. In time of grass cutting operation, the lid is closed, and grass clippings from a duct are collected in the grass catcher through the guide in a guiding position. In time of grass clippings discharge, the grass catcher is detached from the grass collecting duct of the lawn mower, and carried to a grass clippings dump area. Then, the lid is swung open, and the guide also is swung to an open position, to expose the large opening through which the grass clippings are discharged from the grass catcher (see Japanese Unexamined Patent Publication H03-004714, pages 2–3 and FIG. 1, for example).
Instead of a grass catcher being carried by personnel to a grass clippings dump area, a lawn mower may move to the grass clippings dump area and discharge grass clippings from a grass catcher. This lawn mower includes a main container body connected to a lift link mechanism to be swingable about a transverse support axis to switch between a grass collecting position and a grass discharge position. The main container body has an open/close lid swingable about a transverse support axis for opening and closing an opening formed in the rear end of the main container body. A hydraulic cylinder extends between the lift link mechanism and the main container body for position switching of the main container body. A link mechanism is interposed between the lift link mechanism and open/close lid for switching the open/close lid as interlocked to position switching of the main container body. Grass clippings are discharged from the grass catcher by switching the grass catcher from the grass collecting position to the grass discharge position at a high level spaced from the grass collecting duct (see Japanese Unexamined Patent Publication 2001-275438, paragraphs 12–17, FIG. 5, for example). With this lawn mower, backlash or the like could occur in the link mechanism for switching the open/close lid as interlocked to position switching of the main container body, whereby the grass clippings leak from between the main container body and the open/close lid while the lawn mower is running.
A further known example of lawn mowers includes a movable flap disposed in a region between a grass collecting duct and a grass catcher. When the grass catcher moves up away from the grass collecting duct, the movable flap is displaced to a position for closing an opening of the grass catcher, thereby to prevent grass clippings from inadvertently falling from the opening of the grass catcher (see U.S. Pat. No. 6,050,072, Col. 4–6, and FIG. 3, for example). With this lawn mower also, unless the displacement mechanism of the movable flap is manufactured accurately, grass clippings could leak from between the closed movable flap and opening of the grass catcher.